What Are The Top 5 Problems With Fiberglass Pools?
If you are interested in buying a fiberglass swimming pool,
1. Pool Wall Bulging
Years ago, all fiberglass contractors where trained to back-fill their pools with sand. It was industry standard and no one thought anything of it. Little did we know as contractors, that this would create some problems.
As water gathers around the swimming pool, it creates hydro static pressure against the pool. In the same way as I mentioned in my article about liner pools. The hydro static pressure applies large amounts of stress on the swimming pool but typically it is not an issue due to the strength of the pool shell. What does become an issue, is when the water mixes with the back- filled sand. Water mixed with sand changes the characteristics of the sand causing it become liquefied material. The liquefied sand then becomes heavier than the water inside the swimming pool. Soon after, gravity begins to takes over and the liquefied sand begins to self compact and fall lower and lower around the outside of the pool. The combination of the liquefied sand combined the compaction, will begin to apply such a great amount of pressure the walls begin to budge.
We have also found over the years, manufacturers that have not taken care of their pool molds, Â will always result in poorly made pools. Typically having errors in the coping and having unintentionally created bulges in the walls, even before the pool is in the hole.
Prevention: This is a two part fix. All swimming pools not just fiberglass should be back filled with clean 3/4″ stone. The water does not change the characteristics of the stone relieving the stress on the pool walls.  In addition to back-filling with clean stone, your swimming pool contractor also should install a “dry pit” or a “de-watering system.” These systems will allow you to remove most of the water out from around the pool. Clearing your mind of walls bulging.
Find a great pool manufacturer
2. Spider Cracks
Small hairline cracks in the gel coat, that happen due to high amounts of pressure against the surface. This typically happens during the delivery of a swimming or during installation.
During delivery: If the manufacturer has not shipped the swimming pool with proper re-enforcement inside. The risk is higher that the pool will flex or bounce around and cause spider cracks to form. Also spider cracks can form from the pool not being built thick enough. It is super important to not only research your pool builder but also super important to research their preferred manufacturers. We have personally sent swimming pools back due spider cracks from pools being shipped improperly and a swimming pool not made to the promised specs of the manufacturers.
During installation: If an installer mis-handles the pool shell with their machinery, while either lifting or moving it suddenly with out the manufacturer’s reinforcement, may cause spider cracks. The reinforcement inside the pool should not be removed until the pool is ready to be leveled, locked an back filled. Spider cracks may also occur when the contractor is attempting to level off the swimming pool. The areas of the pool that are to low, need to be lifted into proper place. When lifting, if the contractor is not careful about the amount of pressure applied to the pool, they may cause a crack then.
Spider cracks, although are not to common with a good quality manufacturer and an awesome builder, have become accepted. They do not affect the structural integrity of the pool by any means. If they are even visible outside of a few inches from damaged area they do not affect the pools finish either.
Prevention: A good manufacturer that cares about how the pool is made and also shipped. And the best possible builder that pays attention to the installation process and really understands how to maneuver fiberglass swimming pools.
3. Color Fading
Color Fading: Part of buying a fiberglass swimming pool is enjoying the luxurious finish it has. Certainly fading would definitely make anybody disappointed. I mean, I get it, I definitely would not want to see my pool finish fade away either. Who would not care. But it is something that happens to all styles of pool.
As far as fiberglass pools are considered, we are fortunate enough to have not seen to many finishes that fade. Actually it is less than 1% that have faded on us. This is most likely due to the fact that we do install tons of automatic pool covers on swimming pools, which protects the pools from sun damage.
Prevention: Even though we have not seen it happen to much with our pools, does n0t mean it cant happen. There is nothing that can do to prevent this 100% of the way. With that I definitely recommend getting and auto cover installed on the pool to protect it from UV damage. Other than that I would not say to much more because it really has not happened to much in particularly with the technological advances in the fiberglass gel coats.
4. Bad Pool Manufacturer
Coming off of problems 1, 2, and 3. I thought it only appropriate to place this as number 4.
It is so important to KNOW WHAT YOU ARE BUYING! I am not yelling I promise, I just get way to excited 🙂 The swimming pool industry is not nearly as popular as… lets say the appliance industry! So hear me out, in the appliance industry people know about brands like LG, GE, Kitchen Aid, Samsung, Maytag, Kenmore, Amana ETC. (I Just listed those off of the top of my head in about 10 seconds, see! lol) On any given day you can find readily accessible information, reviews and prices on any of these brands. It is not like that AT ALL in the swimming pool industry. There are a lot of bad brands out there that claim they have the best gel coats, chopped fibers, warranties, the most scientists etc. Its actually really easy to get away with crazy claims in the swimming pool industry because of the lack of popularity. No one is really there keeping tabs. I would recommend that you do some heavy research on the manufacturer of your swimming pool.
Prevention: Back to how this is related to 1,2 and 3 of this article. Issues 1 and 2 can be prevented, at least before the pool gets to your house, if your contractor uses a high quality manufacturer. Remember, bulging walls could have been created, due to poorly maintained molds. And spider cracks can easily happen upon delivery with out proper reinforcement. Â Issue 3 is in relation to how well manufacturers spray their gel coat. We have found some manufacturers have issues with fading in different spots due to the inconsistency of the thickness of their gel coat. Now, I know I said fading sometimes can not be prevented, which is still true. But if you choose a good manufacturer that sprays evenly, even if it fades, a pool that fades evenly is much better than it fading in spots.
I would  recommend once you pick a swimming pool contractor, ask to check out older fiberglass pools. See what the finishes look like after years. Look to see if the stairs and walls are bulging; maybe it was back filled wrong or it is was a poorly maintained mold. If anything, it will bring good questions that your contractor should address.
5. Settled Plumbing That Causes Leaks
Alright, I have to take this one back to the back-fill product of the pool; sand against 3/4″ clean stone. If the pool is back filled with sand or any other self compacting product. As the self compacting back fill settles, it applies downward pressure on the plumbing, separating the PVC at the coupled joints causing a LEAK!
Prevention: OK, so as we know from earlier, back fill with clean 3/4″ stone! Do not chance it with other self compacting back fills. In addition, we recommend that any swimming pool plumbing be installed with “hose straps.” We have found that it is best practice to hang the hoses from the top of the swimming pool with “hose straps.” This leaves no chance for the pipes to settle and separate at the couplings, which means less of an opportunity for a leak, YEAH! Man do we as pool guys hate leaks LOL!
So there you have it, the top five problems of fiberglass swimming pools. I hope that you have gained some insight on the problems that exsist with fiberglass pools.